NEET UG 2024 — Thermodynamics

According to the law of equipartition of energy, the number of vibrational modes of a polyatomic gas of constant $\gamma=\frac{C_p}{C_v}$ is ( $C_P$ where $C_v$ are the specific heat capacities of the gas at constant pressure and constant volume, respectively):

A thermodynamic system is taken through the cycle $a b c d a$. The work done by the gas along the path $b c$ is: 

The following graph represents the $T$ - $V$ curves of an ideal gas (where $T$ is the temperature and $V$ the volume) at three pressures $P_1, P_2$ and $P_3$ compared with those of Charles's law represented as dotted lines.  Then the correct relation is:

The equilibrium state of a thermodynamic system is described by A. Pressure B. Total heat C. Temperature D. Volume E. Work done